How to compare two PDF files
Create a visual report that highlights changes between two PDFs.
- Choose exactly two PDFs: the original first and the updated file second.
- Check that each document contains no more than 20 pages.
- Select Compare PDFs and download the PDF comparison report.
Common questions and quick fixes
What do red highlights in the PDF comparison mean?
They mark visible pixel differences between the page images. Changes in text, spacing, images or rendering can all produce a highlight.
Does Compare PDF check hidden text or file properties?
No. This is a visual page comparison. It does not compare document metadata, hidden content or the meaning of the text.
Why are unchanged words highlighted?
Different fonts, page scaling or rendering can change the pixels around the same words. Review the highlighted area in both source files.
Why does my PDF comparison fail?
Select exactly two readable PDFs with up to 20 pages each. For longer documents, split matching sections first. Unlock password-protected files with permission before comparing.
Helpful tip: Use the same page size in both source files to make visual changes easier to spot.